The troopers of two starships have joined forces to terminate a massive bug attack at a Federation outpost. Before the mission can be completed and the survivors evacuated, one ship abruptly departs and goes inexplicably dark. The remaining battle-hardened troopers race to the rescue only to discover that the threat from the bugs is about to hit home.

Federation trooper Johnny Rico is ordered to work with a group of new recruits on a satellite station on Mars, where giant bugs have decided to target their next attack.

The universe of the Halo video game series is expanded in seven short animated films from Japan's greatest anime directors and studios.